my folks did this year ago to one of their bedroom walls. My mom bought flannel flat sheets in red & black plaid. They started at the top & secured them with matching thumbtacks. That's all they used & nothing was distorted or difficult to smooth out. They just tacked as they smoothed/covered the wall. They turned the edges under & you never knew it was a sheet unless someone asked. Of course, mom loved to brag! lol Good luck!